The field of the disclosure relates generally to turbomachinery and, more specifically, to systems for removing heat from turbomachinery components.
In at least some known gas turbine engines, air is pressurized in a compressor and mixed with fuel in a combustor for generating a stream of high-temperature combustion gases. Energy is extracted from the gas stream in a turbine which powers a mechanical load. During operation of the gas turbine engine, various hot gas path components are subjected to the high-temperature gas stream, which can induce wear in the hot gas path components. Generally, higher temperature gases increase performance, efficiency, and power output of the gas turbine engine. Thus, at least some known hot gas path components are cooled to facilitate the gas turbine engine to operate with the increased high-temperature combustion gas streams.
Some known hot gas path components include an airfoil with a cooling system, such that a coolant stream, typically composed of bleed air extracted from the compressor, is forced through internal cooling passages defined within the airfoil. The air is then discharged through cooling holes or passages located at an outer surface of the airfoil to transfer heat away from the hot gas path component. This forced air cooling facilitates the hot gas path components functioning in the high-temperature gas stream. Although some known cooling systems include internal cooling passages, such known cooling systems are generally inadequate at facilitating even or targeted cooling of the airfoil. For example, such known systems generally include long, unidirectional internal cooling passages that generally do not permit reclamation of warmed portions of the coolant stream until well after the cooling capacity of the coolant stream has been significantly diminished. As a result, portions of the airfoil do not receive adequate cooling and are prone to undesirable induced temperature gradients. Such temperature gradients result in suboptimal cooling and efficiency of the airfoil.